Casing seal means for a rotary piston engine

Abstract

In a rotary piston type engine including a casing comprising a rotor housing and a pair of side housings, a sealing member disposed between each of the side housing and the rotor housing for sealing combustion gas from working chambers and engine cooling liquid from coolant passage means in said housings, said sealing member comprising a rubber body and a heat resistant layer integrally moulded with the rubber body and disposed to face the working chamber so as to protect the rubber body against the heat of combustion gas.

We claim: 
     
       1. In a rotary piston internal combustion engine including a casing having a rotor housing and a pair of side housings, said rotor housing having a trochoidal inner peripheral wall surface, said side housings mounted on opposed sides of said rotor housing, a polygonal rotor positioned in the space defined between said rotor housing and said side housings of said casing, said rotor being mounted for planetary revolution and rotation about an axis so as to define working chambers between the circumference of said casing and said rotor, circumferential cooling liquid passages extending axially through said rotor housing and into at least a portion of each of said side housings, and sealing means located between said rotor housing and each of said side housings and positioned between said cooling liquid passages and said inner peripheral wall surface of said rotor housing, the improvement in which each of said sealing means includes at least one seal member formed from a rubber body and a heat resistant layer integrally attached thereto and covering at least a portion of said rubber body, said seal member being positioned with said heat resistant layer interposed between said rubber body and said working chambers so as to protect said rubber body from the hot combustion gases in said working chambers, said heat resistant layer comprising polytetrafluoroethylene. 
     
     
       2. The rotary piston internal combustion engine of claim 1 in which either said rotor housing and each of said side housings has a circumferential groove in the surface facing the other housing, and said seal member is fitted in the groove.